Slowly but surely, the word is
getting out. A cardiac collapse victim
can be sustained with effort for a surprising length of time. The best I have seen so far is three hours in
London
Accepted wisdom has been that the
brain begins to die within several minutes of the heart stopping. This led to an early cessation of effort and
the certain death of the victim. Now we
know that strong cardio will keep the brain alive (and all the other organs as
well) for as much as three hours.
Strong cardio is hard work and
one would need to be spelled in order to maintain the effort. Here it is suggested that the compression be
a full two inches to produce the necessary effects. That may be just playing safe. However, when I suffered a cardiac arrest, my
friend who is a strong body builder, would certainly have maintained a strong
cardio compression stroke and did that until the paramedics arrived. In my case, I went a full twenty minutes
without a heartbeat. I obviously had a
full recovery.
It is curious that I had my
attack in my friend’s apartment within ten blocks of the city’s premier cardio
care facility and he had taken training in Nursing and CPR in particular. I could not have planned it better had I tried. It certainly demonstrated that survival was
very possible and since then eyes have been opened to the prospect of victim survival.
This work now provides us with
the necessary tools to determine if the body is still exchanging oxygen and justifying
heroic efforts to recover the victim.
96 Minutes Without a Heartbeat
New Strategies to Revive Victims of Cardiac Arrest; Improving Odds of
Survival Without Brain Damage
By RON
WINSLOW
A little-known device is shaking conventional wisdom for reviving
people who suffer sudden cardiac arrest: People may be able to go much longer
without a pulse than the 20 minutes previously believed.
The capnograph, which measures carbon dioxide being expelled from the
mouth of the patient, can tell rescuers when further efforts at cardiopulmonary
resuscitation, or CPR, are futile or whether they should be continued. It is
the latest effort that cardiology experts and emergency teams are devising that
aim to improve a patient's odds.
The American Heart Association recently revised its guidelines for
first responders, with particular emphasis on initiating hard, rapid chest
compressions to keep the stricken victim's blood circulating. Rescue squads
increasingly are chilling victims of cardiac arrest with ice packs and other
cooling approaches, a technique known as hypothermia, in order to protect the
brain from injury when blood flow is restored.
Some 300,000 Americans suffer sudden cardiac arrest each year, and
fewer than 10% survive long enough to leave the hospital.
For Howard Snitzer, a 54-year-old chef from Goodhue , Minn.
Mr. Snitzer's rescuers, who rotated every couple of minutes to avoid
fatigue, kept pumping his chest. Thirty-four minutes after he went down, a
medical team from the Mayo Clinic swooped in via helicopter. During the ordeal,
11 shocks with a defibrillator failed to restore his heartbeat.
What kept them going? Readings
"If we didn't have the CO2 readings we were getting, we would have
terminated efforts much sooner," says Bruce Goodman, a flight paramedic
with the Mayo Clinic's Medical Transport unit, which was summoned to Mr.
Snitzer's aid.
Sudden cardiac arrest typically results from a heart attack or an
electrical malfunction that causes a runaway heartbeat. Mr. Snitzer went into
ventricular fibrillation, a quivering of the heart that leaves it without a
pulse.
Of the 300,000 annual cases of sudden cardiac arrest outside a
hospital, 125,000 victims are found too late to be helped, says Michael Sayre,
associate professor of emergency medicine at Ohio State University, Columbus,
and co-author of the American Heart Association's new CPR guidelines. A person
who is down for 10 to 12 minutes without any assistance is almost impossible to
revive. For the others a critical factor in their prospects is whether someone
saw them collapse, called 911 and began effective CPR.
After cardiac arrest, separate actions may be
needed to revive a patient.
·
Chest
compressions (left), at a rate of at least 100 per minute and two inches deep,
are needed to keep the blood circulating.
·
Electric shock
with an automated external defibrillator may help restore the heart's rhythm
·
A breathing
tube inserted into the windpipe allows rescuers to pump air into the lungs and
to detect whether CO2 is being exhaled, a sign that oxygen-rich blood is
circulating through the body
The big worry in sudden cardiac arrest beyond restarting the heart is
protecting the brain. Other organs such as the kidneys and the lungs "can
tolerate longer periods" without oxygen, but the brain is the organ that
succumbs most likely early on," says Roger White, a Mayo Clinic
anesthesiologist who was involved in Mr. Snitzer's case and who is an expert in
management of sudden cardiac arrest.
Rescuers have long monitored patients' breathing tubes for carbon dioxide
to make sure the device was correctly placed in the windpipe instead of the
esophagus. Now for the first time, the recent AHA guidelines, which were
published last fall, call for a more sophisticated and continuous monitoring of
CO2. Just last week, the AHA published course materials to teach emergency
personnel how to use capnography.
The technology records CO2 pressure in millimeters of mercury. Research
by Dr. White and others shows that if the maximum CO2 pressure achieved during
20 minutes of CPR is 14 or less, resuscitation is almost certainly futile. If
the level is above about 25, "you need to keep working at it until you've
exhausted all of your tricks," Dr. White said.
When Mr. Goodman and his co-workers hooked Mr. Snitzer up to the
capnograph upon their arrival, they were impressed with his CO2: It was in the
low 30s. A normal level in healthy adults is between 35 and 45. But after the
effort went on for 45 minutes, Mr. Goodman became concerned. In his 15-year
career as a paramedic, the longest successful CPR case he'd been on was about
45 minutes.
Mr. Goodman consulted by cellphone four times with Dr. White. After
about an hour and 15 minutes had elapsed following Mr. Snitzer's collapse, the
two decided that an additional dose of an anti-arrhythmia drug and one more
shock—the 12th—would be the last chance. CPR continued as those steps were
taken. At the 96th minute, soon after the shock was administered, Mr. Snitzer's
pulse returned.
Mr. Goodman wasn't inclined to celebrate. "I'll be honest, it was
not a great feeling that night," he recalls. "It was a good feeling
that we got pulses back, but there was nothing in history to tell me he would
survive this and that he could recover" with his brain intact. "I
wasn't sure we had done the right thing for him."
About five days later, Mr. Goodman learned that Mr. Snitzer, who had
been treated for a heart blockage, kidney failure and other problems, was out
of intensive care. Mr. Goodman and other colleagues who worked on the case went
to the hospital to visit. Mr. Snitzer was sitting up in a conference room,
talking to his family in a normal voice. "It was a little bit of a shell
shock to see him doing that well," Mr. Goodman says.
In a report on the case published online last month by Mayo Clinic
Proceedings, Dr. White and his colleagues reported that Mr. Snitzer
"experienced a complete neurologic recovery" and described the
episode as the "longest duration of pulselessness in an out-of-hospital
cardiac arrest with a good outcome."
Mr. Snitzer goes regularly to the Mayo Clinic for cardiac
rehabilitation. He says he had hardly any idea what happened to him or how he
came to survive it. But as he learned about the quick response from rescue
workers and how the signals from the capnograph convinced them not to quit, he
said: "I'm a regular guy. I happened to die at the right place at the
right time."
Corrections & Amplifications
A device called a capnograph that can be used in rescuing victims of
sudden cardiac arrest measures levels of carbon dioxide in millimeters of
mercury. An early version of this story incorrectly said it was in milligrams
of mercury.
Write to Ron Winslow at ron.winslow@wsj.com
No comments:
Post a Comment